Radiofrequency Ablation of Papillary Thyroid Microcarcinoma: A 10-Year Follow-Up Study

PURPOSE: To investigate the efficacy and safety of radiofrequency ablation (RFA) for papillary thyroid microcarcinoma (PTMC) after > 10 years of follow-up. MATERIALS AND METHODS: This study included five patients who underwent RFA to treat PTMCs (five lesions, mean diameter 0.5 cm, range 0.4–0.7 cm) between November 2006 and December 2009. The inclusion criteria were histopathologically confirmed PTMCs, a single PTMC lesion without extrathyroidal extension, no metastasis, and ineligibility or refusal to undergo surgery. RFA was performed by a single radiologist using a radiofrequency generator and an internally cooled electrode. We retrospectively analyzed the procedure-induced complications, serial changes in ablated tumors, recurrence, and local as well as lymph node metastasis based on data obtained from medical records and radiological images. RESULTS: The mean follow-up period was 130.6 months (range 121–159 months). Three patients underwent a single RFA session, and two patients underwent two RFA sessions. We observed no procedure-induced complications. Three tumors completely disappeared after ablation, and ablation of the other two tumors resulted in the formation of a small scar that showed long-term stability (mean duration 16.8 months, range 12–27 months). At the last follow-up, no patient showed recurrence or lymph node metastasis, and serum thyroglobulin levels were within normal limits in all patients. CONCLUSION: RFA may be effective and safe to treat low-risk PTMC in patients who refuse or are ineligible for surgery.